kbarber
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Hello,
I'm wanting to use Primetime as a means to find the delay of each net in my gate-level design.
When I issue the report_timing command all I receive is the following error message:
No constrained paths.
I have constrained the clock with the following command:
create_clock -period 10 [get_ports CLK]
I was under the impression that any other constraints were optional?
I've also tried using the report_timing command in Design Compiler. With DC, I at least receive some output - but each net delay is shown as 0.
Below is an example:
n4 has no delay - and neither does any other net - only the fan-out is shown.
Any insight as to why PrimeTime is unable to give any reports (is it mandatory to specify more constrains than just the clock?) or how to report the delay for each individual net in DC (or PT, for that mater) would be greatly appreciated!
Thanks in advance.
-k
I'm wanting to use Primetime as a means to find the delay of each net in my gate-level design.
When I issue the report_timing command all I receive is the following error message:
No constrained paths.
I have constrained the clock with the following command:
create_clock -period 10 [get_ports CLK]
I was under the impression that any other constraints were optional?
I've also tried using the report_timing command in Design Compiler. With DC, I at least receive some output - but each net delay is shown as 0.
Below is an example:
Code:
Point Fanout Cap Incr Path
---------------------------------------------------------------------
input external delay 0.00 0.00 r
key0[2] (in) 0.00 0.00 r
key0[2] (net) 1 1.92 0.00 0.00 r
U131/ZN (INVX0)<- 0.06 0.06 f
n4 (net) 2 5.42 0.00 0.06 f
U24/Q (OR2X1) 0.12 0.18 f
n13 (net) 1 2.59 0.00 0.18 f
U129/QN (NAND2X1) 0.11 0.29 r
t[2] (net) 8 20.34 0.00 0.29 r
U122/ZN (INVX0) 0.19 0.49 f
sbox1_inst/n7 (net) 12 31.53 0.00 0.49 f
U83/QN (NOR2X0) 0.20 0.69 r
sbox1_inst/n14 (net) 4 10.45 0.00 0.69 r
n4 has no delay - and neither does any other net - only the fan-out is shown.
Any insight as to why PrimeTime is unable to give any reports (is it mandatory to specify more constrains than just the clock?) or how to report the delay for each individual net in DC (or PT, for that mater) would be greatly appreciated!
Thanks in advance.
-k